From 92eb783e4d8a69858448bc13d3900d8af93014e3 Mon Sep 17 00:00:00 2001
From: Sheng Yang <sheng@linux.intel.com>
Date: Wed, 21 Jan 2009 16:52:16 +0800
Subject: [PATCH 4/4] KVM: MMU: Map device MMIO as UC in EPT

Software are not allow to access device MMIO using cacheable memory type, the
patch limit MMIO region with UC and WC(guest can select WC using PAT and
PCD/PWT).

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
Bugzilla: 485485
---
 arch/x86/kvm/mmu.c |    9 +++++++--
 arch/x86/kvm/vmx.c |    3 +--
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 2f2b253..81b4492 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -1768,8 +1768,13 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *shadow_pte,
 	if (largepage)
 		spte |= PT_PAGE_SIZE_MASK;
 	if (mt_mask) {
-		mt_mask = get_memory_type(vcpu, gfn) <<
-			  kvm_x86_ops->get_mt_mask_shift();
+		if (!kvm_is_mmio_pfn(pfn)) {
+			mt_mask = get_memory_type(vcpu, gfn) <<
+				kvm_x86_ops->get_mt_mask_shift();
+			mt_mask |= VMX_EPT_IGMT_BIT;
+		} else
+			mt_mask = MTRR_TYPE_UNCACHABLE <<
+				kvm_x86_ops->get_mt_mask_shift();
 		spte |= mt_mask;
 	}
 
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index f4ce1c2..ef25037 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -3716,8 +3716,7 @@ static int __init vmx_init(void)
 	if (vm_need_ept()) {
 		bypass_guest_pf = 0;
 		kvm_mmu_set_base_ptes(VMX_EPT_READABLE_MASK |
-			VMX_EPT_WRITABLE_MASK |
-			VMX_EPT_IGMT_BIT);
+			VMX_EPT_WRITABLE_MASK);
 		kvm_mmu_set_mask_ptes(0ull, 0ull, 0ull, 0ull,
 				VMX_EPT_EXECUTABLE_MASK,
 				VMX_EPT_DEFAULT_MT << VMX_EPT_MT_EPTE_SHIFT);
-- 
1.6.1